.App {
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  right: 0;
  overflow: hidden;
  .main {
    width: calc(100% - 260px);
    height: calc(100% - 60px);
    margin-top: 60px;
    margin-left: 260px;
    overflow: auto;
  }
}
